Switch.



Patented Aug. 21; I900.

No. 656,29l.

. E. w. a. c. HOFFMANN.

SWITCH.

(Application fil'ed Sept. 2, 1899.)

(No Model.)

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ERNST VV-ILHELM GUSTAV CARL HOFFMANN, OF CI-IARLOTTENBURG, GER- MANY,ASSIGNOR TO THE SIEMENS dz I-IALSKE ELECTRIC COMPANY OF AMERICA, OFCHICAGO, ILLINOIS.

SWITCH.

SPECIFICATION forming part of Letters IPatent No. 656,291, dated August21, 1900.

Application filed September 2, 1899. Serial No. 729,326. (No model.)

T at whom it may concern.-

Be it known that I, ERNST WILHELM Gus- TAV CARL HOFFMANN, a subject ofthe Emperorof Germany,residing at Charlottenburg,

Germany, have invented a certain new and useful Improvement in Switches,(Case No. 241,) of which the following is a full, clear, concise, andexact description, reference being had to the accompanying drawings,form- IO ing a part of this specification.

My invention relates to switches, and primarily to that class ofswitches employed for controlling electric subci'rcuits, and has for itsobject the improvement of the construction and operation of switches ofthis class.

In switches of this class as at present constructed a single movablecircuit-controlling portion is employed, and in order to break thecircuit quickly and positively it is neces- 2o sary to actuate themovable portion, usually by strong springs. The sudden jar occasionedwhen the switch-actuating member is brought to rest by striking somerigid portion of the switch-base after having opened the circuit 2 5 isfrequently sufficient to break a switch part. To obviate this difficultyand to decrease the speed with which the switch-actuating portion moves,I preferably movably mount both contact-making parts instead of one, thetwo parts thus receding in opposite directions when the circuit is to bebroken. The speed of the contact-making portions may be decreasedconsiderably.

Generally speaking, my invention comprises 5 a plurality of inclinedsprings forming terminals of the circuit that is to be controlled and arevoluble switch-actuating portion. The switch-controlling elementserves to bring the contacts together,and the springs by their 0resiliency break contact when out of engagement therewith.

In the preferred embodiment of my invention I mount the terminal springsof the switch at one end and so relatively arrange the 5 springs thatthe free end of one is elevated from and placed over the anchored end ofanother. I provide a ratchet mechanism whereby the switch-controllingelement is limited to one direction of rotation. I also mount theswitch-controlling element upona shaft, with which it rotates, but uponwhich it is adapted to move longitudinally. A coiled spring ispreferably placed about the said shaft, which is stiff enough to enablethe switch controlling portion to perform its function and which willyield sufliciently to prevent violent action.

I will explain my invention more particularly by reference to theaccompanying drawings, in which- Figure 1 is a side view of a switchmade in accordance with the invention, the protecting-case beingremoved. Fig. 2 is a view similar to Fig. l with the switch parts andcontrolling element in ,a diiferent relative position. Fig. 3 is a topView of the switch shown in Fig. l with the switch-handle removed, acircuit to be controlled by the switch being indicated diagrammatically.Fig. 4 is a top View of the switch shown in Fig. 2, the

switch-handle being removed. Fig. 5 is a cross-sectional view of thebase on line 5 5 of Fig. 4:.

Like letters indicate like parts throughout the different figures.

An insulating-support a is provided, upon which springs b b and c c aremounted, each at one end, the free end of each spring being opposed toand capable by the resiliency of the spring of being removed from theanchored end of the next spring, the springs thus being spirallydisposed. The springs c c are connected to one side of the circuit, Fig.3, and the springs 19 b are connected to the other side. It is obvious,therefore, that the number of contact-springs might be reduced, but forthe sake of symmetry and to prevent undue wear upon the actuating memberI prefer the arrangement illustrated, by which construction smallmovements only are needed in effecting the control of the circuit. Iemploy a central shaft d, which is prefer ably of square cross-sectionthroughout the major portion thereof, this shaft being rotatablysupported within the base of the switch. A block e is mounted upon theshaft to rotate therewith, but to move longitudinally thereof, the shaftbeing of square cross-section fitting a corresponding square opening inthe block a, the block being pressed toward the switch-springs by meansof a coiled spring f, which is interposed between the block and anoperating-handle g. This coiled spring exerts a pressure upon the blocktoward the switch. The block supports radially-projecting arms h,adapted as the said block is rotated with its shaft successively to comeinto contact with diametrically-opposite springs to actuate the same. Inorder to prevent the shaft from being rotated in a reverse direction, Iemploy ratchet mechanism, one member, in this instance the toothedmember 2', forming part of the base of the switch and serving to engagethe arms 71 of the operating-handle, which thus act in part as pawls.

The operation of the switch will now be evident. When the handle 9 isturned to the right from the position shown in Fig. 1, it will graduallydepress the springs b b, the arms h h moving over the inclined surfaces7c of the ratchet mechanism '5. When the arms h are almost above theanchored ends of the springs c a, they will suddenly depress the springs17 1) into engagement therewith, as the arms will then have passed overthe inclined surfaces 70 of the ratchet and dropped into engagement withthe intermediate surfaces Z, due to the action of the springf. Thecontinuity of the circuit is thereby established, the springs 6 beingwholly and the springs c slightly depressed. The motion of the arms 72,by dropping into engagement with this lower surface Z gives sufficientindications that the circuit is securely closed. When the arms h arerotated farther, they leave the springs 11 1), whose free ends thenrecede from the springs c c, the arms h serving, further, to depress thelatter springs at the same time by engaging the lowermost flat surfaceof the ratchet. By this means I am enabled to effectively break thecircuit by moving the contact portions in opposite directions, no suddenjars being occasioned whereby the effectiveness of the switch portionsmight be decreased.

I do not wish to be limited to the precise construction shown, aschanges may readily be made without departing from the spirit of myinvention; but, 7

Having thus described my invention, I claim as new and desire to secureby Letters Patent 1. The combination with a contact-spring supported atone end and having a free end, of a second contact opposed to the freeend of the said spring, a rotatable contact-springactuating memberadapted to bring the free end of the contact-spring into engagement withthe opposed contact, the said contactspring being arranged in a planetransverse to the axis of rotation of the said actuating member, a shaftwith which the actuating member is adapted to rotate and upon which itis adapted to move, and a coiled spring for thrusting the actuatingmember into engagement with the contact-spring, substantially asdescribed.

2-. The combination with two sets of contact-springs, each spring beinganchored at one end and having a free end, the free ends of the springsbeing normally separated from and opposed to the anchored ends of thesprings, of a rotatable actuating member adapted for successiveengagement with the said springs to effect engagement between opposedsprings, substantially as described.

3. The combination with two sets of contact-springs, each spring beinganchored at one end and having a free end, the free ends of the springsbeing normally separated from and opposed to the anchored ends of thesprings, of a rotatable actuating member adapted for successiveengagement with the said springs to effect engagement between opposedsprings, a shaft with which the actuating member is adapted to rotateand upon which it is adapted to move, and a coiled spring for thrustingthe actuating member into engagement with the contact-springs,substantially as described.

4. The combination with a spring supported at one end and having a freeend, of a second contact opposed to the free end of the said spring, arotatable contact-spring-actuating member adapted to bring the free endof the contact-spring into engagement with.

the opposed contact, the said contact-spring being arranged in a planetransverse to the axis of rotation of the said actuating member, andratchet mechanism for limiting the shaft to one direction of rotation,substantially as described.

5. The combination with a contact-spring supported at one end and havinga free end, of a second contact opposed to the free end of the saidspring, a rotatable contact-springactuatingmember adapted to bring thefree end of the contactspring into engagement with the opposed contact,the said contactspring being arranged in a plane transverse to the axisof rotation of the said actuating member, a shaft with which theactuating member is adapted to rotate and upon which it is adapted tomove, a coiled spring for thrusting the actuating member into engagementwith the contact-spring, and ratchet mechanism for limiting the shaft toone direction of rotation, substantially as described.

6. The combination with two sets of contact-springs, each spring beinganchored at one end and having a free end, the free ends of the springsbeing normally separated from and opposed to the anchored ends of thesprings, of a rotatable actuating member adapted for successiveengagement with the said springs to efiect engagement between opposedsprings, and ratchet mechanism for limiting the shaft to one directionof rotation, substantially as described.

In witness whereof I hereunto subscribe my name this 15th day of August,A. D. 1899.

ERNST WILHELM GUSTAV CARL HOFFMANN.

WVitnesses:

HENRY I-IAsPER, WILLIAM MAYNER.

